Guardian Telecom Inc.
Installation Programming Operation
Merge/Isolate Zone Control System
Page 14
Potentiometer Adjustments on the MICABs
Back Panel access Potentiometers
The Page line impedance adjusting potentiometers for each of the isolated
zones are located next to the Zone connectors on the back panels of both
Master and Slave MICABs. With the Page Line not in use inject a test
signal into the Page Line. Adjust the potentiometer in the Line Balance
Assembly until the signal on the Page Line reads 0.5VRMS. If new
stations are added to a zone, the Page Line impedance of that zone should
be adjusted to adapt to the new load.
See: Figure 6 - Back
Panel Wiring
Connections
Front Panel access Potentiometers
The Merged Page line impedance adjusting potentiometer is located on the
front of the Master MICAB once the Plexiglas is removed. This adjustment
will affect the impedance of the merged page lines. Adjust it when the
system is first set up or when stations are added to the system.
See: Figure 7 - Front
Panel Adjustments
The mixed line signal strength adjusting potentiometer is located at the
front of the MICAB and is accessible once the Plexiglas is removed. All the
audio signals on the isolated and merged page lines are mixed and sent
back to the MICON speakers to monitor requests. A system may have one
to six MICONs. This potentiometer is utilized to adjust the mixed line audio
for the existing load (one to six MICONs). Adjust this potentiometer as
follows:
Using any MICON as a reference station set the speaker volume to a
maximum level.
Adjust the mixed line level potentiometer until the reference MICON picks
up lowest noise.
Page from one of the Page/Talk stations from an isolated zone. Listen to
the speaker volume on the reference MICON (with speaker volume to
max.).
Adjust the mixed line level pot until the speaker on the reference MICON
provides an acceptable audio level (~ 85dB @ 0.5 meter).
Adding or removing MICONs in the system may affect the speaker volume
of the other MICONs. If the volume control in the MICON cannot
compensate for the increase or decrease of the speaker volume, the
system may require re-adjustment of this potentiometer.
The data line Signal Threshold potentiometer is located at the front of the
MICAB and is accessible once the Plexiglas is removed. This adjustment
affects the received data signal strength detection threshold of the MICAB.
Adjust it until the MICAB can detect the instructions sent from the MICONs.
Ten Zone Merge/Isolate System Description
A Ten Zone Merge/Isolate System consists of two MICABs, and a maximum of six MICONs. Of the two
MICABs, one is configured as the master, and the other one as the slave. All six MICONs have the
same status in accessing the MICAB on a first come first served basis. The full capacity of the system
is ten zones. If the setup is less than six zones, one MICAB is all that is required.
The system supports an alarm tone generator, a telephone interface module and line balance
assemblies (omit).
The system has to be set up prior to operation.
